Prognostic value of flotillins (flotillin-1 and flotillin-2) in human cancers: A meta-analysis

Increasing evidence indicates that flotillins which associate with cell infiltration and metastasis are overexpressed in multiple tumors. The prognostic role of flotillins remains controversial. We conducted a comprehensive meta-analysis of published research to investigate the prognostic value of flotillins in patients with cancer. Pooled HRs (hazard ratio) with 95% CIs (confidence interval) were collected to estimate the prognostic value. Twenty-seven studies with 4803 cancer patients were finally identified. The results indicated that: (1) elevated flotillins predicted poorer OS (overall survival) (HR = 2.17, 95% CI 1.87 to 2.52; HR = 1.61, 95% CI 1.44 to 1.81) and DFS (disease-free survival) (HR = 2.41, 95% CI 1.83 to 3.18; HR = 3.01, 95% CI 2.12 to 4.27) in patients with cancer; (2) Subgroup analysis showed that the prognostic value of flotillin-1 on OS and DFS in the investigated tumors were not altered by tumor type (such as digestive system cancers, renal cell cancer, lung cancer, or others), country (China or Canada), cutoff value, detection method, analysis type or paper quality and flotillin-2 overexpression indicates poor OS in human cancers except for nasopharyngeal carcinoma. Flotillins are promising as new biomarkers to predict poor prognosis of patients with tumors. This conclusion needs more clinical studies with different types of cancer to be proven.